code: def test_skip(testdir):
      """Test `skip` flag of `verify_image_cache`"""
      make_cached_images(testdir.tmpdir)
      testdir.makepyfile(
          """
          import pytest
          import pyvista as pv
          pv.OFF_SCREEN = True
          def test_imcache(verify_image_cache):
              verify_image_cache.skip = True
              sphere = pv.Sphere()
              plotter = pv.Plotter()
              plotter.add_mesh(sphere, color="blue")
              plotter.show()
           """
      )
  
      result = testdir.runpytest("--fail_extra_image_cache")
      result.stdout.fnmatch_lines("*[Pp]assed*")
  
file_path: pytest-pyvista/tests/test_pyvista.py
imports: import filecmp
  import os
  import pyvista
label_desc: Use image node_id 5 for calling a global function with example usage: test_skip(testdir) without return types